Aquacultural Engineering最新文献

{"title":"The influence of length–width ratio of an unconventional mobile finfish structure on the drag force and dissolved oxygen: Laboratory experimentation and Computational Fluid Dynamics (CFD)","authors":"Duc Nguyen ,&nbsp;Si Thu Paing ,&nbsp;Sarah Wakes ,&nbsp;Ross Vennell ,&nbsp;Scott Rhone ,&nbsp;Louise Kregting ,&nbsp;Suzy Black","doi":"10.1016/j.aquaeng.2025.102538","DOIUrl":"10.1016/j.aquaeng.2025.102538","url":null,"abstract":"<div><div>Open ocean aquaculture (OOA) offers a number of benefits from inshore aquaculture, such as stronger currents and waves enhancing the water quality. However, conventional static aquaculture systems deployed in the open ocean do not resolve environmental issues such as the effects of heatwaves, or physical challenges such as extreme wave action. Farming fish in a mobile or semi-mobile system would have the advantage of being able to move fish to the best conditions for the fish year-round. The current study proposes an unconventional fin fish structure that could be deployed in the open ocean on either a single-point mooring (fixed), or as a fully mobile (mobile) system. The body of the structure is a square cross-section cylinder shape, covered by water-proof woven fabric cloth, and nets placed at the front and back of the body. This study considers how adjusting the length–width ratio, influences drag forces (important for a mobile scenario) as well as the dissolved oxygen (DO) inside the structure (important for a fixed scenario). This was achieved using flume experiments and Computational Fluid Dynamics (CFD). The volume of the structure is kept at 10,000 m³, current speed at 0.1 m/s and fish stocking density is 30 kg/m³ with the length–width ratio varying from 1 to 6. We found that when the length–width ratio increased, this resulted in the decrease of drag force and an increase of the unhealthy volume fraction (i.e. DO &lt; 70 % of ambient DO) inside the structure, and vice versa. We also found that speed reduction caused by bio-fouling results in an increase of drag force and unhealthy volume fraction. Therefore, it is recommended that the design of mobile structures should balance the demands of the fish as well as the fish farmers which will be dependent on the operation (fixed or mobile).</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102538"},"PeriodicalIF":3.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fish mass estimation method based on adaptive parameter tuning and disparity map restoration under binocular vision","authors":"Lu Zhang ,&nbsp;Yapeng Zheng ,&nbsp;Zunxu Liu","doi":"10.1016/j.aquaeng.2025.102535","DOIUrl":"10.1016/j.aquaeng.2025.102535","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Accurately estimating fish mass is crucial for evaluating fish growth status, enabling precise feeding, and improving aquaculture efficiency. In current aquaculture, invasive measurements may cause certain damage to fish and affect their healthy growth, non-invasive measurements mostly use stereo cameras to capture fish images and extract two-dimensional and three-dimensional features for mass estimation. The calculation of three-dimensional fish features relies on the acquisition of accurate disparity maps. Most current disparity maps are obtained through manual tuning of algorithmic parameters, which not only increases labor and time costs but also introduces a degree of randomness. To address the above problems, a fish mass estimation method based on Adaptive Parameter Tuning-Disparity Map Restoration (APT-DMR) and Multiple Linear Regression (MLR) under binocular vision technology is proposed. Firstly, fish images are obtained using a binocular camera, followed by camera calibration and image correction. Secondly, image processing technologies are used to segment the corrected image to obtain the fish target, and the two-dimensional features of the fish target are extracted. On this basis, the method based on APT-DMR is adopted to obtain the fish disparity map, extract the corresponding key matching points of the left and right images of the fish, and calculate the coordinates of the three-dimensional spatial feature points using the triangular transformation principle, achieving the extraction of the three-dimensional features of the fish target. Finally, fish mass is predicted using the MLR method. Based on the binocular vision technology, the APT-DMR method is employed to obtain the fish disparity map, which realizes the extraction and calculation of the three-dimensional features of the fish. The proposed method effectively addresses the problem that the traditional algorithm needs to constantly tune the parameters to obtain an accurate disparity map. Additionally, a new feature, the fish depth ratio, is introduced to enrich the model representation, and finally, the fish mass is successfully predicted. In addition to saving time and labor costs, the proposed method also effectively eliminates the stress and potential damage to the fish caused by invasive mass measurements. The crucian carp were taken as the experimental object and the proposed method was tested on the real dataset. The results show that the mean absolute error (MAE) is 0.0061, the root mean square error (RMSE) is 0.0084, and the coefficient of determination (R&lt;sup&gt;2&lt;/sup&gt;) is 0.9338. Compared with Polynomial Regression (PR)-Weight, Decision Tree Regression (DTR)-Weight, Random Forest Regression (RFR)-Weight, Back-Propagation Neural Network (BPNN)-Weight, and Support Vector Regression (SVR)-Weight mass estimation methods, the performance of each evaluation metric of the proposed method has been greatly improved, predicting the fish mass more accurately.&lt;/div&gt;&lt;/di","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102535"},"PeriodicalIF":3.6,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Group activity amount estimation for fish using multi-object tracking","authors":"Yiran Liu ,&nbsp;Beibei Li ,&nbsp;Liegang Si ,&nbsp;Chunhong Liu ,&nbsp;Daoliang Li ,&nbsp;Qingling Duan","doi":"10.1016/j.aquaeng.2025.102534","DOIUrl":"10.1016/j.aquaeng.2025.102534","url":null,"abstract":"<div><div>The activity amount of fish can directly indicate its level of health. Quantitative indexes of fish activities provide valuable data for water quality control, disease warning, and fish behavior research, which can enhance factory breeding technology and fish welfare. To address the issue of a lack of indicators for the amount of activity in fish groups and individuals, a group activity amount estimation method based on fish multi-object tracking is proposed in this paper. The FasterNet network is improved by incorporating a branch that learns the features from the previous frame. This method is referred to as Improved FasterNet Fish Tracking (IFFT), and is capable of fast and accurate identification, location, and estimation of the offset of fishes between the two frames in a joint way. Subsequently, a method of activity amount estimation based on grid step is proposed to get the activity index from the trajectories. Moreover, a visualization method is proposed to illustrate the spatial distribution of fish groups. This method utilizes elliptic fitting to calculate the spatial distribution characteristics such as radius, dispersion, cohesion, and polarization. Experiments conducted on the established fish tracking dataset demonstrate that the proposed IFFT achieved a high-order tracking accuracy (HOTA) of 67.54 % and a multi-object tracking accuracy (MOTA) of 92.4 %, surpassing other existing mainstream methods. Furthermore, the average tracking speed reached 20.6 frames per second (FPS). The mean absolute percentage error (MAPE) of the activity amount estimation of fish groups based on the grid step is 0.15 % per frame, indicating a highly accurate estimation of fish activity. The results demonstrate that the proposed activity estimation method of fish groups based on multi-object tracking effectively eliminates the interference caused by water movement. It also achieves a balance between speed and accuracy, enabling real-time quantitative and visual analysis of fish group movement and providing decision support for improving the factory farming process.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102534"},"PeriodicalIF":3.6,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-objective optimization of inlet and outlet in a circular culture fish tank using the GBDT-NSGAII algorithm and computational fluid dynamic","authors":"Shanhong Zhang ,&nbsp;Guanghui Yu ,&nbsp;Yu Guo ,&nbsp;Yang Wang ,&nbsp;Daoliang Li ,&nbsp;Xiaoli Zhao ,&nbsp;Dannie D. O'Brien ,&nbsp;Jui-Che Chiang","doi":"10.1016/j.aquaeng.2025.102532","DOIUrl":"10.1016/j.aquaeng.2025.102532","url":null,"abstract":"<div><div>In a circular culture tank, hydrodynamics plays an essential role for the growth and development of aquatic products in the recirculating aquaculture system (RAS). The challenge of maintaining the maximum effective energy utilization rate and achieving uniform velocity distributions remains a significant hurdle. To solve this problem, a novel multi-objective optimization approach was employed, utilizing the Gradient Boosting Decision Tree-Non-Dominated Sorting Genetic Algorithm II (GBDT-NSGAII) algorithm, to optimize the parameters of inlet and outlet of culture tanks as achieving suitable hydrodynamics. Specifically, the initial circular tank is regarded as the benchmark, four vital parameters of circular tank including nozzle quantities, nozzle diameters, outlet diameters, and inlet angles has been investigated by CFD model. The development of a GBDT-NSGA-II-based model and parameter optimization is conducted to obtain the Pareto front, with the objective of maximizing effective energy utilization rate while minimizing velocity STD. The main results show that: 1) At an inlet velocity of 0.5 m/s, the benchmark successfully establishes dynamic homogeneous velocity fields, while exhibiting a highly pressurized domain in the inlet pipe primarily influenced by the nozzle diameter. 2) The GBDT model demonstrates excellent predictive capability for the CFD database, with an RMSE of 0.002 m/s for average velocity and an RMSE of 0.304 % for velocity STD.3) The diameter of nozzles (12.76 mm) and the number of nozzles (7) have a highly significant influence on both average velocity and velocity uniformity compared to the benchmark model among the 63 groups of optimal Pareto fronts. 4) The optimal inlet-outlet parameter combination mainly includes an inlet velocity of 0.49 m/s and an outlet diameter of 22.26 mm, which improves the energy utilization rate up to 88 % compared to the benchmark model. The GBDT-NSGA-II model, driven by CFD simulation dataset, can effectively replace complex CFD calculations and save computer resources, exhibit commendable performance in accurately predicting the hydrodynamics of circular culture tanks in RAS.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102532"},"PeriodicalIF":3.6,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high-precision and lightweight underwater fish detection and recognition approach based on the improved YOLOX-nano algorithm","authors":"Mengtian Li ,&nbsp;Xiaorun Li ,&nbsp;Shuhan Chen ,&nbsp;Hui Huang","doi":"10.1016/j.aquaeng.2025.102533","DOIUrl":"10.1016/j.aquaeng.2025.102533","url":null,"abstract":"<div><div>In the past few years, the aquaculture industry has experienced a growing demand for in-situ fish detection using live videos from underwater observatory platforms to autonomously monitor cultivated fish and assess their health and growth conditions. To achieve the ideal balance between model size and detection precision, this paper offers a lightweight YOLOX-based fish detection and recognition approach termed Foc_YOLOXn_ASFF. In this study, we introduce Focal loss as a substitute for the binary cross-entropy (BCE) loss utilized by the original YOLOX to train the objectiveness branch, aiming to alleviate the class imbalance between the background and foreground classes. Meanwhile, we focus on moderating the inconsistency across various feature scales by combining YOLOX-nano with the adaptively spatial feature fusion (ASFF) structure to better fuse multi-scale features. Foc_YOLOXn_ASFF remarkably boosts the AP by over 3.6 % from 0.846 to 0.877 compared with the original YOLOX-nano through the implementation of Focal loss and ASFF structure. Foc_YOLOXn_ASFF achieves superior performance with 0.877 AP but only 2.27 M parameters, outperforming the counterparts YOLOv5n and SE_YOLOv5s_DGhost by 1.2 % AP and 7.9 % AP respectively. Extensive experimental findings indicate that Foc_YOLOXn_ASFF for both model size and detection precision is capable of meeting the requirements of practical applications on embedded devices with limited computational resources.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102533"},"PeriodicalIF":3.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrodynamic characteristics of the aluminum alloy net panel in regular waves: An experimental study","authors":"Yu Lei ,&nbsp;Weidong Li ,&nbsp;Xiang Yuan Zheng ,&nbsp;Xiao Cai ,&nbsp;Shan Gao ,&nbsp;Huadong Zheng ,&nbsp;Sheng Zhang ,&nbsp;Xin Liu","doi":"10.1016/j.aquaeng.2025.102531","DOIUrl":"10.1016/j.aquaeng.2025.102531","url":null,"abstract":"<div><div>Copper alloy nets have attracted more and more attention in marine aquaculture, due to their better performance to resist biofouling and corrosion. In the present study, a series of laboratory experiments are conducted to investigate the hydrodynamic characteristics of the chain-link type alloy nets in waves. The wave elevations at different downstream locations of the nets and the wave forces on the downstream net panel are measured to investigate the shielding effects of the upstream aluminum alloy nets. The wave transmission and shielding coefficients under different wave heights, wave periods, and immersion depths are derived. The experimental data show that the wave transmission coefficient fluctuates around 1 (1 ± 0.04), whether only a single net or two parallel nets are placed in water, and the shielding coefficient also fluctuates around 1 (1 ± 0.07) under different conditions. Both two coefficients have weak correlation with wave heights, wave periods and immersion depths of the net panel. It indicates that the shielding effects of such metal nets are negligible. To obtain the empirical hydrodynamic coefficients through test data, a user-friendly numerical optimization scheme is developed. The optimized hydrodynamic coefficients can well predict the wave force on the frame and the nets.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102531"},"PeriodicalIF":3.6,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Establishment and performance of sea purslane (Sesuvium portulacastrum) in marine aquaponics with hybrid grouper","authors":"Miaofeng Yang ,&nbsp;Yongqing Lin ,&nbsp;Shenghua Zheng ,&nbsp;Huidong Zheng ,&nbsp;Fang Yang ,&nbsp;Yingyu Xi ,&nbsp;Donglian Luo","doi":"10.1016/j.aquaeng.2025.102530","DOIUrl":"10.1016/j.aquaeng.2025.102530","url":null,"abstract":"<div><div>Aquaponic systems are sustainable and environmentally friendly, primarily through the recycling of nutrients. However, identifying feasible combinations that achieve favorable economic and environmental performance in a win<img>win mariculture system can be challenging. A novel aquaponic mariculture system was established by combining sea purslane (<em>Sesuvium portulacastrum</em>) with hybrid grouper (<em>Epinephelus</em> sp.), and its performance was assessed. Triplicate experimental fish ponds assembled with floating plant beds of sea purslane (<strong>SP</strong> group) were compared with the control (without phytotreatment, <strong>CK</strong> group) over a 56-day experimental period. The changes in major pollutants in the system and the growth performance of the plants and groupers were analyzed. The results showed that the removal rates of pollutants in the sea purslane aquaponic system were 98.1 %, 97.5 %, 89.9 % and 50.6 % for total ammonia nitrogen (TAN), nitrite nitrogen, total suspended solids (TSS) and chemical oxygen demand (COD), respectively. Furthermore, the removal rates of total nitrogen (TN), total phosphorus (TP), dissolved inorganic nitrogen (DIN), and dissolved inorganic phosphorus (DIP) were 19.6 %, 12.0 %, 18.4 % and 16.2 %, respectively, in the <strong>SP</strong> group. With respect to growth performance, the specific growth rate (SGR) of groupers in the <strong>SP</strong> group increased by 43 % compared with that in the <strong>CK</strong> group. Grouper growth in the <strong>SP</strong> group showed strong negative allometric growth, whereas isometric growth was observed in the CK group. The net growth of sea purslane increased by 4.32 ± 1.64 kg/m², with a relative growth rate of 0.90 ± 0.28 %/d, showing considerable incorporation of carbon via photosynthesis. Moreover, the sea purslane–grouper aquaponics system can be maintained at a low cost and is easily managed. In conclusion, the potential of this innovative marine aquaponic system was demonstrated, and the findings will contribute to enhancing the performance of environmentally friendly mariculture techniques in the future.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102530"},"PeriodicalIF":3.6,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-series growth estimation of sea cucumbers (Apostichopus japonicus) in co-cultivation with coho salmon using time-lapse cameras in field experiments","authors":"Takero Yoshida ,&nbsp;Kasumi Kogo","doi":"10.1016/j.aquaeng.2025.102529","DOIUrl":"10.1016/j.aquaeng.2025.102529","url":null,"abstract":"<div><div>As Integrated Multi-Trophic Aquaculture (IMTA) continues to gain attention, this study investigated the co-culture of coho salmon (<em>Oncorhynchus kisutch</em>) and juvenile Japanese sea cucumber (<em>Apostichopus japonicus</em>) in Kuji Bay, Iwate Prefecture, Japan. The sea cucumbers were housed separately in box cages below the coho salmon aquaculture cages, and the growth was monitored using an underwater time-lapse camera from December 2022 to May 2023. The time-lapse camera was used to monitor the small sea cucumbers with an average body weight of 1.2 g for the initial stage. Semantic segmentation using the Segment Anything Model (SAM) was then applied to the images to separate the sea cucumbers from the background. Body weights were converted from the area of the sea cucumbers in the images. The estimated body weights were plotted over time and compared with the measured body weights. From this, a time-lapse camera can be used to roughly estimate the growth of sea cucumbers over time, which will be helpful to understand the co-cultured sea cucumbers.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102529"},"PeriodicalIF":3.6,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical and numerical modeling of seaweed in oceanic waters","authors":"Henrik Neufeldt ,&nbsp;Christian Windt ,&nbsp;Bela H. Buck ,&nbsp;Kevin Heasman ,&nbsp;Arndt Hildebrandt ,&nbsp;Nils Goseberg","doi":"10.1016/j.aquaeng.2025.102528","DOIUrl":"10.1016/j.aquaeng.2025.102528","url":null,"abstract":"<div><div>Understanding the dynamics of the stress imposed by water motion on seaweeds in oceanic waters is crucial for effective coastal management and the sustainable development of seaweed-based industries. However, the dynamics of highly flexible seaweeds (e.g., <em>Saccharina latissima</em> or <em>Laminiara digitata</em>), driven by its mechanical and morphological properties, poses challenges for conventional fluid-structure-interaction models. This paper provides a comprehensive review of physical and numerical modeling approaches for seaweed hydrodynamics, aiming to identify knowledge gaps and offer guidelines for future research. Methods for determining the physical properties of seaweeds are being reviewed. However, for living organisms, these properties change as a result of age, mechanical impact or environmental conditions. Therefore, we also review the impact of various influencing factors on the physical properties. Hydrodynamic properties of seaweeds (e.g., drag, reconfiguration, shading effects) and the connection with their physical properties will be discussed. Moreover, a comparison between physical and numerical models for the determination of hydrodynamic loads on seaweeds is presented, discussing their possibilities and limitations. Finally, the paper investigates differences in force determination between isolated seaweed, seaweed farms and forests, as well as variations between flow-dominated and wave-dominated environments. The review reveals the challenges in comparing physical and hydrodynamic properties of seaweeds across different studies. It also identifies knowledge gaps in the parametrization of these properties. The recommended guidelines proposed in this paper provide a first framework to address these challenges and minimize variability between studies, thereby offering valuable guidance for future research.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102528"},"PeriodicalIF":3.6,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143578263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hybrid approach towards real-time monitoring of fish distributions in aquaculture net cage","authors":"Qin Zhang ,&nbsp;Biao Su","doi":"10.1016/j.aquaeng.2025.102527","DOIUrl":"10.1016/j.aquaeng.2025.102527","url":null,"abstract":"<div><div>Cage based salmon aquaculture has grown substantially over the last decades, however it is still, to a large degree, relying on experience-based production regime today. Advances in the digital transformation of the aquaculture industry will improve the ability to monitor, control and document the production systems, and facilitate knowledge-based decision making. In this paper, a combined instrumentation and interpreting solution is proposed and tested for monitoring fish distributions in aquaculture net cage. Farmed salmon in a full-scale sea cage are simulated by an individual-based fish model. And real-time behavioural changes are introduced and determined by data-driven parameter identification, thereby reflecting observed fish distributions from a set of single-beam echosounders. This forms a hybrid approach to combine the interpretability of physics-based models with the automatic pattern-identification capabilities of advanced deep learning algorithms. The performance of a tentative instrumental and model setup is evaluated by comparing with measured fish density data, while providing more detailed information such as the number and swimming speed of the fish, which are notoriously difficult to quantify using conventional solutions. The proposed hybrid approach is considered to be suitable for developing a more comprehensive fish monitoring system to be used on a daily basis in marine aquaculture.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"110 ","pages":"Article 102527"},"PeriodicalIF":3.6,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}